The guys at devKitPro.org released libnds 1.3.5 today. For the moment, do not use this with Woopsi-based software. For some reason, this library breaks Woopsi. Woopsi locks up when it reaches the call to swiWaitForVBlank(). I have no idea why it does this yet; all I know is that everything was working fine with libnds 1.3.4 and below.
EDIT: Further testing reveals that DeSMuMe locks up at the swiWaitForVBlank() when running Woopsi. No$GBA ignores all input, but otherwise runs as normal. Ideas runs Woopsi normally. I imagine that this indicates changes in libnds’ code that aren’t emulated properly in DeSMuMe and No$GBA.