Exploding Docking Port

[Brigonius]

Hi I have a problem on my Minimus Lander.

Every time i try to undock the Landing Module from the Command Module the whole Ship explodes.

It is a Apollo Style Launcher.

Here is a Link to the Dropbox Save file: https://www.dropbox.com/s/9obtw0fjl6b7dsd/quicksave.sfs?dl=0

I dont know why this .... is Exploding when i try to undock. The docking after the Apollo like Start was withaut problems.

If you have a solution to my Problem thank you in advance.

by the way the craft file. https://www.dropbox.com/s/700orerxmafxdyv/Kerpollo.craft?dl=0

kind regards Brigonius