Was unable to attach any files to new wpdm posts, similar to others in the forum once I uploaded the file it would appear successful and no error message, and upon checking the filesystem and post meta table, the files did indeed upload but the post meta was blank.
Upon further investigation, it appears that in the FileSystem->absPath function, your calling realpath to resolve any symlinks but later on in allowedPath your checking against a few different paths that weren’t ran through realpath. So allowedPath ends up returning an empty string if the WordPress directory happens to be symlink. I’m using Bitnami’s fairly popular WordPress package, which happens to use a symlink. So this might be a common enough issue for other users.