HELP!! AWS vs GWS vs TWS

I have the following issue: sometimes my log get stuck due to scale and stuff so the STW values become useless. As backup i have the SOG coming from the GPS. Which are the values related to the True Wind i can look at? I think TWS and TWD are calculated using the STW so they become useless as well? Can i tell qtvlm somehow not to use STW but SOG to do the calculations? Thanks in advance for the support!