Thank you for all the help, guys!
I got it now working.
As Barkhorn said, the game freeze can easily be avoided by deleting last.quick file.
And the 70% crash is caused by a faulty stationary.ini of part 7 of WAW, as gwalch said. I replaced it by the one in part 6, too and it works.
Gotta go testing now :))
Better fix for the Part 7 WAW issue:
1. Reload Part7 WAW
2. Open the file "#WAW\STD\com\maddox\il2\objects\stationary.ini", search for "[Command_and_Control]" section, delete everything below that line and replace it with the following content:
FAC vehicles.stationary.CandC$FACUnit 1
AFAC vehicles.stationary.CandC$AFACUnit 1
GCI(m) vehicles.stationary.CandC$GCIUnit 2
GCI(ft) vehicles.stationary.CandC$AGCIUnit 1
RCGCI vehicles.stationary.CandC$RCGCIUnit 2
Vector vehicles.stationary.CandC$VectorUnit 1
OBS vehicles.stationary.CandC$OBSUnit 1
CW vehicles.stationary.CandC$CWUnit 1
FUG202 vehicles.stationary.CandC$FuGUnit 2
FUG218 vehicles.stationary.CandC$FuG218Unit 2
FD2 vehicles.stationary.CandC$FD2Unit 2
SN2 vehicles.stationary.CandC$SN2Unit 2
SN2b vehicles.stationary.CandC$SN2bUnit 2
Naxos vehicles.stationary.CandC$NaxosUnit 2
Flensburg vehicles.stationary.CandC$FlensburgUnit 2
AImkIV vehicles.stationary.CandC$AImkIVUnit 1
AImkVIII vehicles.stationary.CandC$AImkVIIIUnit 1
AImkX vehicles.stationary.CandC$AImkXUnit 1
AImkXV vehicles.stationary.CandC$AImkXVUnit 1
Serrate vehicles.stationary.CandC$SerrateUnit 1
Monica vehicles.stationary.CandC$MonicaUnit 1
GTW vehicles.stationary.CandC$GTWUnit 2
GNR vehicles.stationary.CandC$GNRUnit 1
Corkscrew vehicles.stationary.CandC$CorkscrewUnit 1
Window vehicles.stationary.CandC$WindowUnit 1
Jammer vehicles.stationary.CandC$JammerUnit 1
RO vehicles.stationary.CandC$RadioOperatorUnit 2
NAV vehicles.stationary.CandC$NavUnit 1
OBOE vehicles.stationary.CandC$OBOEUnit 1
H2S vehicles.stationary.CandC$H2SUnit 1
Error vehicles.stationary.CandC$ErrorUnit 1
Aimpoint vehicles.stationary.CandC$AimpointUnit 1
SPR vehicles.stationary.CandC$SPRUnit 1
ASD vehicles.stationary.CandC$ASDUnit 1
ASG vehicles.stationary.CandC$ASGUnit 1
ASVmkIII vehicles.stationary.CandC$ASVmkIIIUnit 1
ANAPS4 vehicles.stationary.CandC$ANAPS4Unit 1
Taki vehicles.stationary.CandC$TakiUnit 2
RESCAP vehicles.stationary.CandC$RESCAPUnit 1
SAR vehicles.stationary.CandC$SARUnit 1
DZ vehicles.stationary.CandC$DZUnit 1
Arty(g) vehicles.stationary.CandC$NGSUnit 1
Arty(n) vehicles.stationary.CandC$NGS1Unit 1
Barrage vehicles.stationary.CandC$BRGUnit 1
Box vehicles.stationary.CandC$BoxUnit 1
Fire vehicles.stationary.CandC$FireUnit 2
Refuel vehicles.stationary.CandC$RefuelUnit 1
RdmPlanes vehicles.stationary.CandC$RandomAircraftUnit 2
RdmPlanes2 vehicles.stationary.CandC$RandomAircraft2Unit 2
RdmGround vehicles.stationary.CandC$RandomVehiclesUnit 2
RdmGround2 vehicles.stationary.CandC$RandomVehicles2Unit 2
RdmWeather vehicles.stationary.CandC$RandomWeatherUnit 1
DynWeather vehicles.stationary.CandC$DynamicWeatherUnit 1
StmFront vehicles.stationary.CandC$StormFrontUnit 1
RdmTime vehicles.stationary.CandC$RandomTimeUnit 1
RdmSkill vehicles.stationary.CandC$RandomSkillUnit 2
RdmTrains vehicles.stationary.CandC$RandomTrainsUnit 2
RdmShips vehicles.stationary.CandC$RandomShipsUnit 2
RdmShips2 vehicles.stationary.CandC$RandomShips2Unit 2
Spawn vehicles.stationary.CandC$SpawnUnit 1
SLD vehicles.stationary.CandC$SLDUnit 1
SLD2 vehicles.stationary.CandC$SLD2Unit 1
Ambush vehicles.stationary.CandC$AmbushUnit 2
CityLights vehicles.stationary.CandC$CityLightsUnit 1
LowRecon vehicles.stationary.CandC$LowReconUnit 1
HighRecon vehicles.stationary.CandC$HighReconUnit 1
Ground_Attack vehicles.stationary.CandC$LevelUnit 1
Landing vehicles.stationary.CandC$LandingUnit 1
DynStream vehicles.stationary.CandC$DynamicStreamUnit 1
Bomb vehicles.stationary.CandC$BombUnit 2
DynamicRescue vehicles.stationary.CandC$DynamicRescueUnit 1
DynStrike vehicles.stationary.CandC$DynamicStrikeUnit 1