Did you not download the RPG VXACE RTP or something?
It took me a couple of hours so let me save all Joiplay players some major headaches, I'll be deleting my old posts, ok so why your game isn't working? Simple, joiplay has fked up haha not even joking, ok we should all know by now there's some translation errors in files that were included in the zip folder, however if you open Joiplay go to top right 3 dot's and into settings, scroll to the bottom it says 'clear runtime packages" tap that to delete all RTP data (yes annoying) then try to launch the game from its icon it'll ask you to install the RTP for vx ace, and do that once the RTP is reinstalled it'll replace the files included in the games directory with the correctly named files from the RTP package you just installed thus most errors will be instantly fixed. Your welcome.