On my MH BB I noticed that the middle string on several notes are run almost straight through across the braidge and don't have the parallel zigzag that other strings do. That is it looks as if there is no side bearing against the pin.

The notes in question sound off and different from the surrounding notes. Is this irregularity the cause of the off sound and Is this a defect in the piano?

you should be able to look at the bridge and tell if the string has moved from the original position. Sounds like it may have. It shouldn't be straight

String has not moved from original position. Distance between pins is not equal. Middle pin is drilled closer to one of the outside pins.
Technician sent by dealer came and looked at it and said it was not affecting the note. ANy thoughts?

From what you describe, it sounds like the piano wasn't built according to the design. In clear terms, a manufacturing error. Whether or not it constitutes an actual problem or not is hard to tell from a distance.

You don't give us much information, but it sounds like you perceive a tonal problem arising from the bridge pin's location, while the dealer tech does not. In that case I suggest talking to the dealer directly, and if that is not helpful I would contact the manufacturer. At some point you may want to get an independent second opinion as well.

Good Luck