HTC Desire :: Post-rooting Many Programs Won't Install Or Launch

I just installed a custom ROM (LeeDroid 2.1a with A2SD+), which installs Froyo version of Android. (Apps install on an EXT3 partition of the SD Card, that the phone thinks is internal memory). However, roughly 25% of apps don't work (ie. Swype, HTC's More Widgets (ie. Dice), TypoClock) . Whether I use Sense or LauncherPro, the same result. Either they don't show up in the app drawer (but can be seen in Applications), or can't be launched (via Quick Info). The apps installed via the Android Market show as installed, but the OPEN button is greyed out.These are apps that worked before on 2.1 Eclair. So with no more info than "Cannot launch application", I can't figure out if its Froyo or the custom ROM (LeeDroid A2SD+) that's the "root" of the problem.