Default Xperia Play boot loops every time something is flashed via CWM

Hi, I've been having some problems with my Xperia Play getting stuck in a boot loop after flashing anything, or restoring a backup in CWM. This includes mods, like Adrenoboost, and the NXT Lockscreen, to themes. I have the Xperia Play R800x with an unlocked bootloader (via unlock code from Sony) and I'm using stock 2.3.3 Gingerbread, with the stock Kernel. I boot CWM by hotBooting LuPuS with Fastboot. I'm not really sure what to do because I really want to install these mods, and because restoring my nandroid backups also gets it stuck in a bootloop, I have to reflash the stock .ftf with FlashTool and reroot it every time.