So thats the EA app asking for a repair. Have you tried running the CnCNetYRLauncher.exe instead?
Theres a campaign selector that will bypass the EA app on the Beta branch of CnCNet. You can follow these instructions here to enable it:
Hey - what renderer have you selected in the CnCNet client options? More info here on where to find this - https://forums.cncnet.org/topic/6866-frequently-asked-questions/#comment-53290
https://cncnet.org/tiberian-sun
The downloads here are complete since its freeware and includes the renderers like ddraw automatically. Maybe just give this a go first
You would need to register an account with them and then request it. Bit of an outdated web page but think it works once signed up
Anyway glad its sorted for now 👍
Try https://mapdb.cncnet.org/yr/d7ddc0102055f038edd1846815a974736470bd96.zip
Theres a lot of variations here https://mapdb.cncnet.org/search.php?game=yr&search=extra small