First download and install Xmouse.
http://www.highrez.co.uk/downloads/X...tonControl.htm
Then allocate bottom 3 buttons to an unused key. (On the drop downs select Simulated Keystrokes). For instance:-
Middle Button = {NUM0}
Left X Button = {NUM.}
Right X Button= {NUM/}
Using Setkeys
Go back to prev cam = NumPad 0 (x60)
Get depth under sub keel = (Crew) NumPad / (x6F)
Commands_en.cfg
Put in additional gobacks eg:
[Cmd17]
Name=UZO_camera
Ctxt=1
MnID=0x3F020014
Key0=0x55,,"U"
Page=0x28000000,3718
GoBack=Conning_deck_camera
[Cmd16]
Name=Periscope_camera
Ctxt=1
MnID=0x3F020003
Key0=0x72,,"F3"
Page=0x26000000,3702
GoBack=Conning_tower_periscope
[Cmd60]
Name=Captain_log
Ctxt=1
MnID=0x3F020012
Page=0x35000000,3744
GoBack=Interior_fore_camera
And many more.
Result
Middle Button will give you additional go-backs
Left X Button will switch the GUI on/off good for 3D views.
Right X Button will ping the bottom and give depth.
I use this and wouldn't do without it, hope this helps.