The workaround I’ve used for the blank panel bug is to remove the plugin’s submenu. The bug happens when opening a panel from the submenu not from the panel. Remove the submenu and the bug can’t be triggered. I wrote about it here (in the other thread about all this): http://forums.creativeclouddeveloper.com/t/uxp-entrypoints-setup-loads-same-panel-always/8026/7
Philip