bolotnik, I looked at your save file and screenshot. Unfortunately, it's too late for you to take action now, :( but if you have save files, at least you won't have to start from the beginning. Where the guard won't let you pass, you need to go there no later than day 147, and you'll get the attack skill of 4 when you enter the Stronghold (move east, then north). Regarding the save file: you needed to go along the secret path south of the lake, next to which the road runs from the north. You need to look carefully everywhere, as in some places the path is disguised with resources or something else lying in the way.