@schorsch89 I tested out the insecure connection and it worked with no problems.
The insecure zip file has the files
cacert.pem
xxxx.pem
xxxx.key
ta.key
xxxx-TO-IPFire.ovpn
in it but you only need the xxxx-TO-IPFire.ovpn file as it contains the actual ca, cert, key and ta directly in the .ovpn file. You can see this if you open the .ovpn file with a text editor.
I just imported the xxxx-TO-IPFire.ovpn file into OpenVPN for Android and it created the profile. I then selected it and the connection was successfully made and I could confirm that I was connected on the IPFire server OpenVPN WUI page.
I also was able to ping a vm machine on my green lan.
So both the secure and the insecure connections work with OpenVPN for Android.
These were the steps I took.
On the OpenVPN for Android screen there is an icon of a white box with a downwards pointing arrow… I press this and it opens a file searcher on my android phone. I then navigate to the directory I have stored the config files on and select the .ovpn file, which is the only one highlighted.
The app then goes to the Convert Config File screen and you can accept or change the Profile Name that it suggests.
I then press the tick nark at the top right hand side of the app screen.
I am then on the app page showing all the profiles that have been created. This now contains the one I just created.
I press the profile name I just created and the connection is successfully made.
Is the above sequence of steps what you are following. If not can you give more details of the steps you are taking to import the profile.