I was hoping to avoid spending more money on games that i already had.
If i had to purchase, then C&C Ultimate seemed the best option. Did see that on steam, and then it disappeared from the store a couple of hours later. Haven't seen it back in the store for almost 2 weeks now. If it does come back to the store, then i might purchase it despite already having the games and despite the workaround below.
I tried the link provided above, but it just takes me to some weird site that i don't understand. If it is indeed C&C, then it's a version of C&C but not as i know it.
I thought i'd give installing and running the DVDs i had anyway for Tiberium Wars and Tiberium Twilight, and running them in compatibility mode. Doesn't quite work, but with some support from EA Games and a few tweaks, i've been able to play these 2. I'll probably try the same with the other ones i have at a later date.
Thanks for the comments above all.