Issue connecting to old (OpenVMS) systems

Hello,

Windterm seems very interesting so i'm trying to use it. One thing i need is to connect in SSH to old systems (OpenVMS) and i have issues.

If i use WindTerm 2.5.0 depending on term type :
VT100 or VT102 : seems OK but when i press functions keys (F10 for exemple) nothing happens (might be normal in VT100 ?)
Any "higher" term i get a lot of different control chars displayed on screen ( ESC["v , CSIK , CSI22, CSI;7m , CSIm , CSI22A and so on... however Functions keys work properly)

If i use WindTerm 2.6.0 pre-release 4 ssh session doesn't even establishes and i have the error :
Received SSH_MSG_DISCONNECT: 2:Postponed channel in CHANNEL_EOF.
The session is disconnected, press Enter to reconnect.

Any chances there is a work around or that i could help fix that for a future release ?