Finally! I did some major changes in a new blank-template_v1.mfa (it's a .mfa file with a LVL Edit's level loading engine).
From now enyone will be able to make a standalone game way easier without separate files from LVL Edit. I'll provide some simple examples soon. Also did some important one event fix for LvlAssetsLibDir (a big problem in fpp_example.mfa). No need to worry about backslash at the end to preview level correctly.

LvlFileDir - Your level file full path,
LvlAssetsLibDir - Assets folder full path,

LvlFromAltString - this checkbox gives the ability to load level directly. You must then specify level file directory and assets library directory to be loaded at the start of frame,
LvlFromImport - this option just reads level and assets library paths from LVL Edit's import.ini file,
FullscreenFromConfig - reads fullscreen mode from LVL Edit's import.ini file,
FullscreenFromMfa - mfa has a priority to decide going fullscreen.

Screenshot below:

If You found any difficulties using it - feel free to ask here! I'm improving it.