MinimServer-0.8.2a-x86.spk on DSM 5.1

[Meffy]

Hello Simon. Just updated Synology DS412+ to DSM 5.1 and tried to install the new minimserver package "MinimServer-0.8.2a-x86.spk" but when i try to install it i get a massage "Action failed".Can not install it. The older package still works on new DSM 5.1 though, but can not install the newer minimserver package. I don't dare to uninstall the older minimserver package "MinimServer-0.8.2-x86.spk" to try to install the new package in case that i won't be able to install it att all after uninstall.
Any hint how i can install the new package would be appreciated.

Thanks in advanced!
Meffy