We recommend using the mobile or tablet viewer to watch your race until tonight, and using the strategy tab in the header, not quick strategy, to set driver strategy. All builds are playable, but there are two GUI quirks that need working around if you use anything else:
1) Fuel on quick strategy is not updating in real time when pressed - both in the app and on the web viewer. This is only a bit confusing, and means the value only changes when you release the button, but it doesn't have any other effect.
2) The strategy panel in the web version of the game appears mis-aligned, and as if there is nothing there sometimes. To fix this you just need to click the previous/next stint arrows above the strategy and it will re-align correctly. That's all.
That is why the best place to do strategy right now is in the mobile or tablet app, in the header strategy tab (not the quick strategy tab). This requires no adjustments or advice... it just works... as the rest should, and they will later after we patch them.
We have been trying to get this resolved for a few hours but unfortunately it will be like this for the next 8-9 hours now, until we get another chance to work on it. This forewarning and guidance is the best I can do to make the situation go a bit more smoothly in the meantime.