Which AI limitations do you mean Slyspy?
The first part questions whether the engine is really new, the second part mentions a new graphic engine. RTW is a bit more than just a new graphic engine (doesn't say it's perfect or even better, but it's different). I'm not a coder nor a PR manager: I wouldn't claim everything is new- actually it would be sad when the wheel (be it round or square) has to be re-invented again and again- but more changed in the engine than just graphics. That does not mean some glitches can't pop up again: a Volkswagen beetle can run out of gas, a Nissan can do too.
Virtually open source: there are some conflicting powers, some of them are within the players (fear for cheats). No, I don't make it up. Others are up in the 'office'. I've no clue what the reason is, but things are not always moving into the direction modders want to see. There may be commercial reasons: CA makes a product, where's the competition?, and has to be careful about giving away. There may be technical problems, you may recognise it: it should work, but it doesn't! Only this case is processed? Fixate it and don't touch or the whole thing turns unstable -> no mod. Fix it? Creating software is not like digging a hole in the ground, just work and get there.
I recall an interview in a game magazine about VI, or maybe it was about MTW? The retail CD would include modding tools. Don't believe newspapers, it wasn't there (apart from the mapeditor). But tools were released later, by fans and CA. And more tweaks could be made to MTW than STW.
Looking at the whole evolution of the TW series you can't deny that CA is not working/trying to make it more 'open'.
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