"stay up-to-date with the latest developments" → Keep current on recent updates
For "legality", possible variants could be admissibility. For "varies depending on your location and local laws", maybe differs based on your jurisdiction and regional regulations. Then "using the ROM in compliance with copyright laws" can be altered to operating the application within the bounds of legal standards.
The term "vast library" would be immense repository, etc.
"stay up-to-date with the latest developments" → Keep current on recent updates
For "legality", possible variants could be admissibility. For "varies depending on your location and local laws", maybe differs based on your jurisdiction and regional regulations. Then "using the ROM in compliance with copyright laws" can be altered to operating the application within the bounds of legal standards. ANIME V1.3 -PD- ROM
The term "vast library" would be immense repository, etc. "stay up-to-date with the latest developments" → Keep