B737 way point change in MCDU will cause P3D V4 to crash

[penta_a 429]

was flying today LOWI-EGLL and every time I try rearranging flight legs in MCDU (when trying to insert/change way point) P3D V4 crashes with following event report;

Faulting application name: Prepar3D.exe, version: 4.0.28.21686, time stamp: 0x594a7255
Faulting module name: ucrtbase.dll, version: 10.0.15063.413, time stamp: 0x5ba8b66e
Exception code: 0xc0000409
Fault offset: 0x0000000000072208
Faulting process id: 0x226c
Faulting application start time: 0x01d308e85f37763c
Faulting application path: F:\Lockheed Martin\Prepar3D v4\Prepar3D.exe
Faulting module path: C:\Windows\System32\ucrtbase.dll
Report Id: 0db2410b-681d-45dd-a3b8-a8baf124f92e
Faulting package full name:
Faulting package-relative application ID:

is it something at my end?

anybody having same problem