There is a way you can increase the priority that hand morphs are set (or is it facial morphs this effects, i forget, maybe it's both, probably both).
Browse to your SL install folder, (probably "C:\Program Files\Second Life"

Open the folder "app_settings"
Backup the file "floater_animation_preview.xml"
Open "floater_animation_preview.xml" in your favorite editor
Search for 'name="priority"' without the single quotes
A few lines below you will find 'max_val="4"'
change it to read 'max_val="5"'
Save the file.
This will not effect the max priority of the animation (it's still only 4) but it will effect the priority for the morphs.
If you screwed up, the client will crash when you open the preview floater.
The client does not need to be exited for changes to have effect (though the preview floater should be closed). This file is hot swappable (most of the xml files in this directory are).
On a side, some of the messages in "alerts.xml" are kinda funny, my favorite is for "ChangeLindenAccess"