transaction match problem/misbehavior

[Ethy H. Brito]

Hi people.

I'm a home user of gnucash 1.8.9 for about a month. Used to run Quicken before.
First of all I'd like to say I am not comfort with accounting jargon in english, second sorry if I may sound confuse. That's because I realy am.

I have this problem when matching transactions with the OFX data I download from my bank every week.

There is this every friday government tax called CPMF in my country. 
The CPMF was shown as new unmatched transaction at the first time I did the matching two weeks ago.
The problem is GC does not show it at transaction match window as a new one anymore despite the fact I can see it inside the OFX file with differents number and value from last week. I think GC is confusing the new CPMF with the old one (already reconciled). I now always have to insert it manually at account register window. 
Is that correct? 
Can't it  be done semi automaticaly anymore like the first time transaction match window saw CPMF ? 
Or even better: what am I doing wrong?

What is the logic GC uses to match a transaction? I mean does it first compares 'Description' fields and then values and then 'Number' or does it use another logic?

Another question is why GC does not show the transacion number at transaction matching window? Some times GC mismatch transactions of the same value and I can only see that (with some luck) at register window. For example I have this 50 bucks withdrawal and a check of the same value. GC took the withdrawal from OFX value and marked the check as 'm'! 
I have to say I forgot to register the withdrawal (that would have been shown as a new unmatched transaction. Wouldn't it?).

Thanx.
All the best

-- 

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