iNyar

Sorry if it has already been responded or if it's a stupid question, but I really don't understand something : some spaces in Avernum are impossible to access because there's a "magic blok/cube" bloking the way. For example, I'm now in Tranquility, and in the Sentinel Workshop, I can't access the button to open the secret door to get the Magery spellbook since there's a blok avoiding me to access to the small room where the button is. More problematic, I can't access the second floor of Shankar's Tower (so I can't realize Shankar's quest), among other things. So, could someone explain me why those bloks are there : restriction because I missed something before ? bug ? restriction because of my class of player ? Or is there a way to remove those bloks ? Thanks a lot in advance