I have both ProSwitcher 1.0 (with libactivator 0.9.3) and Kirikae svn.152 installed. I've got ProSwitcher to activate with a downward swipe, and Kirikae with the double-home-tap activation. No problems and they seem to play nice together.
A few caveats:
1. The downward swipe option for activation was removed from libactivator for now (apparently at the request of BigBoss to make it more compatible with SBSettings). Hopefully, it'll appear again soon. Until then, there's still plenty of other options to activate. (My downward swipe still works since I activated it using a Beta, but ironcally, I don't have an option to remove it anymore.)
2. ProSwitcher 1.0 does not work inside a Categories/CategoriesSB folder. Once inside, the PS icon does nothing and bounces back to the Springboard. To make matters worse, trying to then remove PS from inside a folder wipes out the contents of the folder itself, forcing you to re-spring and add the folder's icons back manually (not sure if this is a Categories bug or not). In any event, do yourself a favor and do not put it in a folder for now. You can either hide the PS icon (with SBSettings or Poof) or just put it on a page on the Springboard.
ProSwitcher is an amazing piece of work. Hard to believe it's free. Many thanks to Ryan Petrich and the ProSwitcher team! Now I can App switch in style!