Sorry I couldn't reply immediately, thank you for being so understanding and supporting.

Now, where i deleted the file from is a very good question.
I understand as well from the dozen of forum entries I've read that should have sorted the issue, and my guess is due to a conflict of the several zotero versions installed, a copy (or copies) of it must still be somewhere.
to answer your question, what i did was open the options in word, go to the add ins, manage word add ins, go and then, since the two zotero files i could see there, 'zotero.dot' and 'zotero.dotm' were not removable, i looked the file full path below it.
mine read 'c users username appdata roaming microsoft word startup zotero.dot
now, followin this path, i could not find it. I'm definitely not an expert but promise, this is also the first time i have to write in a forum in many years, i can follow instructions form tutorials online. it was just not there. i then proceeded to look for it in 'my stuff' in my computer (a minute of silence for windows 10 please, so far i find it dreadful) and i found them..as two word files, like actual word blank pages, which perplexed me, but still. they had the same name and in properties they showed the same path , c user etc. so i tried deleting them but it said 'not possible in use etc'. everything was closed, no word files open. check, tried again, nothing, and so on a few rounds. then i had an idea (from here on I didn't follow any tutorials, in case I messed up, my bad) i right clicked to see if had any other options, i was naively hoping for something like 'show where they are opened' and saw instead that i had the option to 'shred them' with mcafee.. it was too much of a temptation, i killed them with no remorse.
surely that would be it, right? wrong. again. even after shutting down/on again.
after that i have to admit i kind of lost it and after fruitless research online and having tried every advice i found about it, i kind of started going rogue. i tried manually deleting the whole pattern, like getting rid of the folders roaming microsoft etc, since they were empty, and i found out they were in users, in another folder at the same level as my username, called "default.migrated' and would then follow with the supposed path, appdata etc.
by then i was totally confused, and cancelled everything out of frustration (i know). needless to say, after restarting the computer and even emptying the bin (that how desperate i was,) nothing.

anyway, trying to stick to the point: yes i manually deleted them (any research for zotero.dot files came back negative afterwards), yes i did restart everything, computer, word program, etc, plus the 'fix it' troubleshooting i ran for word from the programme's offcial support page was done afterwards. i am told it resets word as it comes as default options, so it should be more than just restarted even.

regarding having to disinstall, i don't mind disintalling zotero/firefox temporarely, which i have done already, as i just started using it so it's relatively empty. what i want to do is, since i am going to use it presumably for the next four years of my degree, make sure it will run smoothly from now on.. disinstalling word might be a slightly more complicated issue as i have to admit i have no recollection about how i purchased it, if it was integrated or if i bought it as a package at the same time when i bought the computer, i just remember it being there from day one, i would have no idea how to prove again it's original etc like keys and so on, unless it automatically detects that.. i would have to look into that.
what i am seriously considering though is running back to windows 8, since this is major problem #3 since the update a mere 48h ago, hence the upcoming mental breakdown. so if you think of suggesting that, don't hold back, i am open to it.
i just need to fix this as i am sure there is a solution, i just can't see it and it drives me insane.

i think you sorted this out!!

So i somehow wasn't aware of the existence of hidden files (my bad, sorry) i enabled them as you said, immediately found the path, the folder was empty. word was still showing both buttons. i downloaded again zotero standalone and the chrome plugin, then went back to see if the files appeared. The did, and i proceeded to delete zotero.dot, (that i realized from the description it's for an older version of word, if i would have seen this yesterday i would have tried with just this one, i couldn't figure out which one I needed to keep so i shred them both).
Again it wouldn't let me delete it saying that the file was open somewhere (word was closed), so I has to shred it again through mcafee. still, it worked, the file is gone.
now if i open word, i only see the 'zotero' option in the toolbar.
first my heart sank when I tried and use it and it said "zotero cannot communicate withh firefox etc', but then I thought maybe it wants zotero standalone opened first? it did!
so, the current situation is:
zotero standalone installed, zotero extension for chrome installed, zotero add in present in word, zotero.dot file deleted, zotero.dotm file where it should be. The zotero extension worked on chrome when i tried saving an entry, and, provided zotero standalone is launched before trying to use it in word, the word add in seems to work too.

do you think we can considered this sorted? if you confirm that the 'cannot communicate with firefox' message is to be expected if the standalone isn't opened, so everything is working as it should and should be reliable for the foreseeable future, i'll be happy and grateful as one can be!!

Yes, this is all sorted. It's just an outdated error message, which is a bit confusing, but meant to just yell you that zotero isn't open.

I'm not certain about the macro settings, but you shouldn't need to enable every time, so try a more permissive setting our see if there's an option to whitelist zotero