[Crochetty]

I am trialling Notation Composer and am really keen for it to work well so that I can make the decidion to purchase. Most of the features that I require seem to perform rather well. There are a few glitches but I am giving Notation the benefit of the doubt here and assuming that some (at least) are due to the variable quality of midi files - for example, misnaming instruments or even putting the composers name and details down in the spaces reserved for instrument names.
There are two more problems, the first being irritating but I will tolerate it if I must: This is an odd tendency to show a key signature at the beginning of each stave in the usual way but then follow it with "natural" symbols followed by the necessary sharps or flats all the way through the piece as a way of reinstating the original key signature. Can this be rectified - or avoided when making sheet music from midis?
The most serious problem is a real disappointment: Why does composer throw randon notes into the bar in which I am working on an existing arrangement - and even into the next (empty) bar. And why, when I select all the right buttons to start a new bar with a dotted minim, does it it insist on inserting an undotted minim followed by two semiquavers - plus an additional note that I didn't want (not even the same pitch) and all linked by slurs which have to be deleted before the notes can be corrected. Then, when I am correcting those notes it starts inserting random notes into the next bar? If this problem cannot be avoided then Composer is not worth buying as all the other features that work reasonably well are available in Musician.
I am using a one year old laptop with loads of spare power and memory and running Vista with all the relevant updates.
Please can somone advise me how to overcome the problems, especially the last one.

Crochetty.