When comparing Engine 001 Game Maker vs Skyline, the Slant community recommends Engine 001 Game Maker for most people. In the question“What are the best game engines for beginners and non-programmers?” Engine 001 Game Maker is ranked 15th while Skyline is ranked 30th. The most important reason people chose Engine 001 Game Maker is:
An amazing minimal download size at around 100mb.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Light weight
An amazing minimal download size at around 100mb.
Pro Easy to use
Engine 001 allows you to get to making games quicker since you aren't putting allot of time into figuring out complicated interfaces.
Pro Visual scripting
By using pre-build behaviors\actions and more you can 'program' your game by simply 'linking' they in the editor.

Pro Great tech support and friendly community
A growing community that is always helpful with dev response times averaging less then 24 hours. Often less than 12.
Pro Comprehensive WYSIWYG editor
Skyline provides a straightforward drag and drop development environment that can be customized to suit individual preferences. Playing the game and animating the scene can be done from within the editor at any time.
Future versions will allow extending editor's functionality with plugins and offer an official way of trading custom plugins.
Pro Highly affordable licensing
Skyline's commercial edition costs just £40, has no royalties or earning limitations and includes 2 activations per license purchase and a year of free updates.
Pro Runs well on lower end machines
Skyline can be run on a machine with 2GHz Dual Core CPU, 2GB of RAM and Nvidia's 9800 GT (or equivalent) GPU. While, obviously, higher specs are recommended, it's reasonable to expect around 60fps on small scenes with these specs.
Pro Excellent terrain editor
The Terrain editor is easy to use and will include features such as hole cutting.
There is a differed lighting render for internal scenes, which makes creating multi light and beautiful/atmospheric scenes so much easier.
All the tools for the terrain are in one place such as placing road/paths, vegetation, billboards, and the settings are easy to locate and change.
Planned features include:
Hole cutting in terrain and
Terrain paging.

Pro Low learning curve
Making a game in the current top engines is hard work, making something small and basic in Skyline is not. Easy to learn drag an drop model placement and editing supplemented with easy to follow video's on forum make the process straightforward.
Pro Full global illumination
Including image based lighting.
Pro Has a free version
A free version that's limited to non-commercial usage and lacks a few features is available.

Pro Impressive water render
Rendering of a water plane looks fantastic and is easily edited for different effects.
Pro Artist-friendly
The schematic editor is designed to make it easier for non-programmers to create games.

Pro Asset store
Not much in it at the moment but is starting to grow and will continue to grow with an increase of users.
Pro Constant development and regular updates
There are many additions to the engine that are on the road map such as multi threading and tree physics.
The feature list is constantly evolving with each user request and idea put forth.

Pro Support for custom editors
Skyline has a custom editor that gives the user of making their own tools for use directly in the editor to develop their games. All the editors are made using the Qt Designer and programmed in lua inside the engine itself.
Pro OSVR support announced
Open-Source Virtual Reality support is in development.
Pro More editor's
Shadow editor.
Weapon Class Editor.
Mesh Editor.
Advanced Mesh Editor.
GUI Editor.
Script Editor.
Environment Editor (volumetric clouds and day night cycle, lightening, ocean settings, height fog).
Particle Editor.
Path editor.
Schematic editor.
Navmesh editor.
Material editor.
Pro Lots of learning resources
The documentation is been rewritten and follows a structure like a course.
Introduction to > Level designer with examples > Artists
There is also video tutorials, video examples and video tutorial series been produced.
There are user created demo scenes, examples and more.
Pro Visual GUI/HUD Dditor
Making HUDs and GUIs has never been easier
Pro PBR Workflow
Full PBR workflow, your not stuck to Secular or Metallic it has both
Pro One on one private support with engine developers
Can contact the Skyline developers and they will always respond and help as fast as they can.
Cons
Con Windows only
The editor is Windows only, no OSX or Linux versions are planned.
Con 3D features may not be enough for some users
The 3D capabilities of the engine are a bit limited (for today standards), and some of the times you'll need to work around to create something.
Con Not for beginners
Even those few tutorials don't teach you the very basics, and first you must learn the basics somewhere else (the submitted pros are by professional guys).
Con No successful/ good games
Just ask them about games made with this engine and you will see that even if you find some good games, those are mostly simple/small ones.
Con Poor performance
If you want to use more than a few actors/light/events, or you're trying to get a pretty look, you will get a significant drop in frame rates. This is especially true if you want to implement a moving light (something like a flashlight).
Con New tricks for getting more money
As it don't have enough tut, and they don't wanna make more, so they just add some new services about one on one help which that cost 40$ for a hour.
Con Small number of tutorials
There are only a few tutorials that never go deep and when you ask them about more and better ones, they will direct you to a new service which is $40 for one hour of learning.
Con They don't fix the bugs for you quickly
If you encounter a bug or problem and report that as bug report, it will take about 1 week to get any answer, and if they solve that, the fixed version will just come up with next update for engine which that isn't be soon and no specific time , so maybe you have to wait for one month.
Con Some workflows can be confusing
Sometimes you have to do a time-consuming workaround to just do a simple function.
Con HTML5 export is poor
There are significant drops in frame rate; some bugs that can even ruin your game (also, looks like just run on firefox).
Con No IAP or Ads support
Are you a mobile developer? If so it's good to know that it has export for ios/Android but no support for IAP or Ads.
Con Free Version currently not available/severely limited when available.
The free version has massive amounts of features functionality removed, including the ability to compile anything standalone.
The free version is currently (as of November 2017) not available until the next major release.
Note: some of what is below is open to change, this is the coming set of changes.
The price will be jumping from $40 to £99.99 ($132.32) for the lowest tier able to build a standalone. This tier will not be able to remove the engine splash screen.
The next tier will be £199.99 ($264.66).
Con No C++ SDK
Con Small community
There is a small but helpful community that are constantly creating video tutorials and one member is creating a FREE ebook to make the transition to the engine simpler.
Con Currently limited to targeting PC
Mobile targets are planned.
Con Still in beta
Not all features are fully implemented yet.
Con Lacks occlusion culling and lightmapping
This is been added in a future update, however a date of this update hasn't been given yet.