@IanB: Ooooh. That's a nice and clean solution. Alas, I'd really like a Double-Tap-thing like it was in TapTap ('cos RCtrl+m and even worse RCtrl+n are still quite awkward key-combos to use), so I tried to do it with
RapidHotKey. Which kinda works although it's quite an ugly script...
; thanks to https://autohotkey.com/board/topic/35566-rapidhotkey/
~RShift::RapidHotkey("^c", 2, 0.1) ;COPY
~RControl::RapidHotkey("^v", 2, 0.1) ;PASTE
RapidHotkey(keystroke, times="2", delay=0.2, IsLabel=0)
{
Pattern := Morse(delay*1000)
If (StrLen(Pattern) < 2 and Chr(Asc(times)) != "1")
Return
If (times = "" and InStr(keystroke, """"))
{
Loop, Parse, keystroke,""
If (StrLen(Pattern) = A_Index+1)
continue := A_Index, times := StrLen(Pattern)
}
Else if (RegExMatch(times, "^\d+$") and InStr(keystroke, """"))
{
Loop, Parse, keystroke,""
If (StrLen(Pattern) = A_Index+times-1)
times := StrLen(Pattern), continue := A_Index
}
Else if InStr(times, """")
{
Loop, Parse, times,""
If (StrLen(Pattern) = A_LoopField)
continue := A_Index, times := A_LoopField
}
Else if (times = "")
continue := 1, times := 2
Else if (times = StrLen(Pattern))
continue = 1
If !continue
Return
Loop, Parse, keystroke,""
If (continue = A_Index)
keystr := A_LoopField
Loop, Parse, IsLabel,""
If (continue = A_Index)
IsLabel := A_LoopField
hotkey := RegExReplace(A_ThisHotkey, "[\*\~\$\#\+\!\^]")
IfInString, hotkey, %A_Space%
StringTrimLeft, hotkey,hotkey,% InStr(hotkey,A_Space,1,0)
backspace := "{BS " times "}"
keywait = Ctrl|Alt|Shift|LWin|RWin
Loop, Parse, keywait, |
KeyWait, %A_LoopField%
If ((!IsLabel or (IsLabel and IsLabel(keystr))) and InStr(A_ThisHotkey, "~") and !RegExMatch(A_ThisHotkey
, "i)\^[^\!\d]|![^\d]|#|Control|Ctrl|LCtrl|RCtrl|Shift|RShift|LShift|RWin|LWin|Alt|LAlt|RAlt|Escape|BackSpace|F\d\d?|"
. "Insert|Esc|Escape|BS|Delete|Home|End|PgDn|PgUp|Up|Down|Left|Right|ScrollLock|CapsLock|NumLock|AppsKey|"
. "PrintScreen|CtrlDown|Pause|Break|Help|Sleep|Browser_Back|Browser_Forward|Browser_Refresh|Browser_Stop|"
. "Browser_Search|Browser_Favorites|Browser_Home|Volume_Mute|Volume_Down|Volume_Up|MButton|RButton|LButton|"
. "Media_Next|Media_Prev|Media_Stop|Media_Play_Pause|Launch_Mail|Launch_Media|Launch_App1|Launch_App2"))
Send % backspace
If (WinExist("AHK_class #32768") and hotkey = "RButton")
WinClose, AHK_class #32768
If !IsLabel
Send % keystr
else if IsLabel(keystr)
Gosub, %keystr%
Return
}
Morse(timeout = 400) { ;by Laszo -> http://www.autohotkey.com/forum/viewtopic.php?t=16951 (Modified to return: KeyWait %key%, T%tout%)
tout := timeout/1000
key := RegExReplace(A_ThisHotKey,"[\*\~\$\#\+\!\^]")
IfInString, key, %A_Space%
StringTrimLeft, key, key,% InStr(key,A_Space,1,0)
If Key in Shift,Win,Ctrl,Alt
key1:="{L" key "}{R" key "}"
Loop {
t := A_TickCount
KeyWait %key%, T%tout%
Pattern .= A_TickCount-t > timeout
If(ErrorLevel)
Return Pattern
If key in Capslock,LButton,RButton,MButton,ScrollLock,CapsLock,NumLock
KeyWait,%key%,T%tout% D
else if Asc(A_ThisHotkey)=36
KeyWait,%key%,T%tout% D
else
Input,pressed,T%tout% L1 V,{%key%}%key1%
If (ErrorLevel="Timeout" or ErrorLevel=1)
Return Pattern
else if (ErrorLevel="Max")
Return
}
}
Thank a TON for your support so far.
, I wanted to ask if there is any chance that you might take a look at this? Does this even occur on your Windows7 or am I the only one?
I have no clue as how to detect a non-detected double-key-press but still I'd give it a try. 
now the Shift-Key doesn't work "on its own" anymore, so I cannot Shift keys at all. FAIL