I think the D6 Star Wars was the one I played years back in my university days. If that's the Keith Baker, Bill Slaviksec version, then yeah, I really enjoyed that.
I don't think I've played any later edition of Star Wars.
I am happy that WFRP 4 is using the D100 system. As a GM it's very easy to explain to new users. And 2nd ed is the system I've been running in a weekly game for the last 8 months on roll20.
For me the percentile system and stats and the careers are what gives WFRP it's flavour. It's pretty easy to translate 1st ed scenarios, though I play in a pre Storm of Chaos version of 2nd. Mainly because it's more in line with the WFB setting that has been around since 4th ed WFB in the early 90's which sort of retconned or invalidated a lot of WFRP1 stuff.
I tried 3rd, but it felt more board game than roleplay game, and the with the stance tiles and various coloured dice it got confusing. I lied the adventures and information provided for 3rd, and from the dice mechanic, I kind of liked that a success could go spectacularly well, or succedd but something then goes wrong. Or a major fail could still have a successful side-effect. Like other systems that have critical success or failure, this also gives a hint of how to twist the side effect to not always double-down. I also liked that there was a party co-operation mechanism, which helped reign in the dumbass "But that's what my character would do" rubbish
There are things that I would possibly like to see done differently, or improved. I hope there is a forum set up on Cubicle 7's website soon so that we can possibly influence things a little but it will be well into development by now.
I'd make a couple of changes at character creation. Being able to roll for the stat values, plus a couple extra, then assigning the best of those stat rolls to your favoured stats, instead of rolling each stat and being stuck with it. Even with Shallya's mercy in 2nd, no player I've played with has ever liked playing a character they know is below average. Also I think they way buying equipment is done with the various is fine, but it involves a lot of rolling for each item and for each quality. It would be better to roll to see if a particular type of trader was available, then that unlocks a range of items.
Having played using Roll20 for the last 6 months, I hope cubicle 7 has support for a character sheet and things for the game on there.