Didn't watch the video. However, there's a button to call for the pitstop, which you're supposed to press to request pit. Did he press it or just went into pits directly?
Flags fixes and improvements are not included yet. In terms of scaling, looks like its actually a small penalty, based on the Trux's testing yesterday and a few others on the WMD forums (maybe about 0.5 sec slower than QRW). Looks like AI is just slow on some tracks/cars, which is a separate issue and will not be solved for now as it requires AI racing line and speed tweaks.
Day 1 patch will include some performance fixes and some other minor bug fixes AFAIK.