Is it ok to offset boxes?

There are a couple downsides to doing this. If you get driving rain - some water will get in. Also, you are more likely to get robbers if the hive isn't strong.

It works in a pinch. Personally, I like propping the lids a bit for an additional entrance...

I prop the lid as well, especially when they are on a flow. Gives them their choice of entrance. I have noticed that it seems they come in the top and go out the bottom...LOL. whatever works for them!

I have done it several times. My bees were not all that interested in using the gap for some reason. They usually just posted guard bees all along the gap.

I also noticed that with foundation they didn't draw out the frames as they got closer to the gaps. I think that with drawn comb they filled it (I can't remember for sure as I stopped doing this several years ago since the bees didn't seem that interested).

Screened bottom boards will provide all the benefits with none of the drawbacks. Foraging bees give their loads to house bees who process and store it anyways, so I don't think the "faster access" consideration to the colony interior means much to the bees from a practical standpoint. SBBs or top entrance for my money; robbing SUCKS.