Yes, that is a limitation of collision checking, not a bug.
Just don't set the speed to a high value.
There are many reasons why your game can't be played in test mode.
Most probably - you have windows defender restricting it from launching an EXE from the editor. You can actually just use a bat file (or create a shortcut) and put "-file YOURPROJECTNAME" as argument to launch your project. The exe should already be in the "projects" folder. If there is none - that is the reason for being unable to test your game.
Actually, hitscan attacks are working as intended. I'm pretty sure it was kinda borken in RGM or worked in a strange way. Not a complete compatibility, I know, but it would take many tweakings to get this right.
The bug with projectiles is known, there is also a problem with projectiles speed.
Attack range is also a known bug.
You can reach me in Discord on OFPSC server: https://discord.gg/ATaVGt9YQ9
Just ping me or KeshaFilm in the english chat and I'll send you a PM when I'll see it.
The source code is messy and is not recommended to be read by anyone )
No, really. It has a long legacy pieces that I never got to remove and is in any way held by ducktape and prayers.
The real name is Easy FPS Editor as I didn't think of anything better. I might release the soure code in future, but not now.
I wonder though; why would you need it?