There is a bug in pocket plus: for some themes, the background for the menu of the close button is completely white. Since the text color is white, this makes it nearly impossible to use the menu.
I just found a solution to solve this and wanted to share it, in case someone else would have the same problem:
-select the theme you want
-add the following registry key (for example with Total Commander):
HKEY_CURRENT_USER\Software\Microsoft\Today\
--> add a DWORD:
name: UseStartImage
value: 1
if you don't want to add this registry value everytime after changing a theme, you can edit the themes if you have a program to edit cab files, for example "WinCE CAB Manager". Since themes (.tsk files) are in fact just .cab files with another extention.