[Resolved]  BMC — Misleading octroi rules

Yesterday on 21.01.09, i was taking a pc and monitor from a nationalied bank's branch at khopoli to thane. i am employee of the said bank hence i decided to carry it by my own car from khopoli to thane alongwith a delivery letter duly signed by the branch manager of the khopoli branch.

While at airoli, i decided to pass thru airoli creek bridge and to go to wagle ind. estate, thane via mulund (e) as this is shortest and fastest route to thane. i paid toll at creek bridge but at the end of the bridge, bmc octroi officials stopped me to pay octroi on used faulty pc. i showed a letter of the branch manager, khopoli written to the regional manager at thane for getting that pc repaired by their office.

But the bmc octroi officials raised an objection to pass thru mulund to thane (as mulund is under bmc). i enquired about escort, but he said that "it is a long process and you will have to fill some form no.18 or so, instead you should return & go via kalwa" and disallowed to enter in the bmc area.
Ultimately, i took u turn, again paid toll on creek and returned to thane via kalwa.

Now, my querry is...
1. whether it is compulsory to go via kalwa eventhough my article does not attract any octroi or so?
2. am i not allowed to enter bmc with non commercial items.
3. what is so called 'long procedure' of filling-up of form no.18 or whatever for escort, if applicable.
4. what if i would be required to pick-up my engineer at mulund (e)? again to go to mulund from thane?
5. whether the concerned octroi official had exploited me?