Welp, I'm more active on steam than here, because of reasons.
Project Retail is about fixing or creating some of the mistakes or forgotten stuff that Gearbox made for it's expansions, "trying" to make it look most valve-ish as possible.
I also want to try the same but reversed, using gearbox assets (mostly ps2/dc) so they can be played both in HL and BS/OP4, making a proper and legitimate "hd" look.
I'm active a lot on Steamcommunity.com if you want to keep track of this mod check the activity feed on steam everytime I'm playing BS/OP4