okay here's the tutorial, download this file first :
https://www.mediafire.com/file/vb7ynb456wt98av/Sonic_Wii_U_Decomps.zip/file
then acquire the RSDK files of Sonic CD, Sonic 1, and Sonic 2 legally.
extract Sonic_Wii_U_Decomps.zip and open it's readme file, that file shows how to set up the...