Chrome update unworkable

I had Chrome portable all set up and working beautifully on my thumb drive, with all extensions functioning optimally.

Then yesterday when it opened it said an update was available. I didn't see any harm in updating it since I had installed it only two weeks ago. However the result was disastrous. It basically stopped working for me; namely, pages took FOREVER to load.

I uninstalled it and tried reinstalling the original setup file I downloaded 7/24. But something is still seriously amiss. Pages still take forever to load and the program itself takes forever to start up. Not at all the behavior it displayed before the update.

Any suggestions as to how I can create a completely clean slate and get rid of whatever is mucking up the works? I'm due to go out of town in a few days and was relying on this browser to function as it was before the update.

P.S.: One additional question: Does the size of the thumb drive matter when it comes to performance of installed portable apps? I started out using an 8 GB drive and so far have filled up 5 GB. However the computer I'm using presently has an Intel i7 processor with 8 GB RAM (running Windows 7 Pro). So I do not think this drastic slowdown of Chrome since yesterday's update would be influenced by size of drive. However should that be the case, I can move everything to a larger, 15 GB thumb drive.

Thanks,