now that you mentioned this, i had a relook at both versions of the gerber files w the gerber viewer and realized that in the 1st version (ie adda.sol), the sol layer was not lined up with the other layers. it layed opposite, like it was mirrored compared to other layers.
being new in this area, i thot this is the way things are. in the revised version, every layer lined up. hmmm....not sure how the 1st version ended up that way, but guess i've learnt something new today.
any tip/recommendations for the slot 'problem' I mentioned earlier? Thks!