Are you using SKSE 1.6.6 (for skyrim 1.8.151)? Are you use SBW (borderless window, etc) [later version of SBW auto detect skse and can mess-up skse's ability to read commandline args] Also, do you have multiple skse dlls in the root of your skyrim folder, if so remove all but the latest version (skse_1_8_151.dll)? One more, thing you can look in the same folder that your game saves are written to (it is probably one folder up from it) and look for SKSE/skse*.log (this might give you a clue as to what is happening)