Please HELP - Data Grid Template disappeared

[UKMC]

Hello altogether,

I have the following strange problem:

I developped a stack containing a datagrid with form-style.
I defined a form-template including script and everything worked beautiful.

Some minutes ago I re-opened the stack and the functionality did not work anymore.

I opened the property inspector and the row template couldn't be opened anymore.
As well the text in field "row behavior" was grey, the stack "Data Grid Templates 148....." is not findable on the computer.

Does anyone know what happend and what can be done to fix the problem ?

Best regards and thanks for your help in advance


Ulrich

P.S.:
Yesterday, I tried to install mergDatagridScroller, what did not work (see other posting)
But this was done within another stack, not this one.
In spite of this this exoperiments should not have any influence, but one never knows...