Попробуй вот
SOLUTION: It is only missing a registry entry.

1. Right-click on your desktop and hit New - Text Document.
2. Name the file "Fix.reg", confirm the extension change.
3. Right-click on Fix.reg and click Edit to open it with Notepad.
4. Copy-paste these seven lines into the file in Notepad:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Enterbrain \RGSS3\RTP]
"RPGVXAce"="C:\\Program Files\\Steam\\SteamApps\\common\\RPGVXAce\\rtp"

[HKEY_LOCAL_MACHINE\SOFTWARE\Enterbrain\RGSS3\RTP]
"RPGVXAce"="C:\\Program Files\\Steam\\SteamApps\\common\\RPGVXAce\\rtp"

5. Replace the paths specified with the actual path to your RPGVXAce\rtp directory (note the double-backslashes), save the file and close Notepad.
6. Double-click Fix.reg on your desktop and click Yes, then OK.
7. Delete Fix.reg
Или же кириллица в путях.
Или же поробуй установить ртп сам.