mRemoteNG 1.7 Beta 1 improved common problem with focus when PuTTY sessions are used. Unfortunately some issues still exist. When 2 or more PuTTY sessions are opened and user switches to mRemoteNG by Alt-Tab, clicking on tabs makes no effect. Steps to reproduce:
1) Start nRemoteNG 1.7 Beta 1
2) Open 2 connections using PuTTY
3) Switch to another application
4) Switch back to nRemoteNG window (using alt-tab or by clicking on PuTTY's area of window)
5) Click on tab with inactive session - it does not make it active.
The workaraund is to click on Connections pane and then clicking on tabs starts working again.