1). When I double click a .flp file without the FL beta already started, the startup sound gets muffled, but if I just open FL then it plays fine.
2). If I open a project file that uses an audio file in either a sampler or an audio clip object that isn't in the right place, if I hit "ok" for the content library to search for the files, it reports the following error:
An error occured while reading the FLP file. it may be corrupted, or some plugin caused an error while opening.
Afterwards, FL will not open new projects until it is restarted.
...after further testing I've found this also happens in FL10.0.8.