There is two types of graphics in ctp series:
-Sprites - what you atually see in the map with movements and all
- And pictures - All picture you see in the GL or in othe Intrface screens
The sprite (wich are the most dificult to get) are exacly the same in ctp2 as it in ctp1. So just get the spriteID number in ctp1 and look for the GU** in the sprite folder and add an extra number to it (ctp uses 2 numbers while ctp2 uses 3) and it is ready to b used in ctp2. As for the marine you dont have to worry its sprite is already in ctp2 database as a unused sprite. I just dont have the number right now.
As for the pics are in tga format in ctp1 just like ctp2. yet ctp1 uses a lot of pics in differents sizes while ctp2 uses only three in the sizes of 160 x 120, 36 x 24 and 24 x 18.
So just resize them from ctp1 and again it is ready to be used.