Today was meant to be the day: After years of hoping that the TLJ will get a sequel, and months waiting for book 5 to come out before starting it, I could finally sit in front of my computer and enjoy it!
But sadly, seems I can't enjoy it (yet) 

I'm running OSX Mavericks on a mid-2011 21" mac
with an AMD Radeon HD 6750M 512 MB
20GB RAM
and quadcore 2.5GHz i5 CPU (I5-2400S)
while not the best gaming machine, it's never given me trouble (being an adventure gamer myself); I've even played Witcher 2 EE/Bioshock 2/Deus ex 3 with very high settings, with no issues whatsoever - but seems DFC is giving me a lot of trouble!
lag issue:
1)The game is sluggish whether I run it at the lowest possible settings/resolutions, or everything maxed out (even though there is some slight difference in the frame-rate, the lag is there)!
What is strangest is that when the game is "minimized" in the background everything stays sluggish; moving the cursor, scrolling, everything lags as if something is crunching my CPU! The Activity Monitor doesn't show any stress though: CPU utilization 5-10%, lots of free RAM too... Same behavior even when everything is at the lowest setting.
visual glitch:
2)In the starting location (
Spoiler
) there are some visual artifacts. At first I thought it was volumetric light gone wrong - some unsupported GL_EXT_, but changing it from low to high and vice versa had no effect. Actually, any setting that I tried changing, had no effect. I even went to the .plist file to disable bloom/flare/and manually 0 the volumetric light, but to no avail (besides whenever I enter the game, it overwrites the .plist changes I've made from Xcode).I've attached the Unity console log and a screenshot of the artifacts.
I'm out of ideas; Anybody who could come up with some suggestion? (other than ditching my poor old imac)
Thanks!
-Fotis