About residential permit expiration: The way this is written in the 2009 IRC is misleading if you read it superficially. What it actually says is that you have to start work within 180 days of the date that the permit was issued and once work has started, work must not stop for more than 180 days. If you can't show progress within a 180 days period (!), you may apply for an extension documenting why you stopped. My permit was issued early 2010 and I made sure to have an inspection showing progress at least every 180 days. Total time of construction will be 3 years (I have another 180 days to go approx.) and I will own a mortgage free house, which I could not have afforded (even with a mortgage) had I paid a builder to construct it within 180 days. The local building department specifically explained to me that I have to schedule inspections not more than 180 days apart for the permit to stay active. Otherwise it would effectively impossible to build DIY while earning a living with a full time job. And no, the neighbor's visual inconvenience does not trump my property rights (it helps that my property is secluded, though). The city has adopted a more stringent energy code after 2010 but my build is grandfathered into the previous one that was valid when the permit was issued.

My suggestion would be to put the tiles on a backerboard per David's comments and then frame that. There are hardware fittings that are used primarily for glass or lucite panels - 'standoffs' we call them but I am not sure what the correct term for them is - I am pretty sure that Outwater has them if you can't get them locally. Anyway - if you dimension your frame correctly then you should be able to drill a hole in each corner of it and into the grout of the backsplash. Screw your standoffs into the backsplash and then attach your framed tile art and you're off to the races ! If you want to take it down later it's very easy to patch four small holes in the grout invisibly. Here is a link that might be useful: http://www.outwater.com

I have two options that may work. Since the door is steel, it probably has an adjustable sill. The adjustable sill will allow you to reduce the door bottom weatherstrip. Remove the plugs and adjust sill upward. Measure height gained and remove that much from bottom of door weatherstrip. Remove the door and lay on edge. Trim weatherstrip with scissors. The other option may annoy you. It's possible to install a stop on the top exterior side of threshold and a bulb weatherstrip on lower edge of door which will allow you to remove the bottom weatherstrip. Or, get something thin at WalMart. :)

Seedling roots should not be allowed to dry out, whether under lights and heat mats or outside in the sun( as I am unaware of your current set up). But I have found that they need lots of water in the hot weather we have in India. Somehow if they are browning at leaf tips, I feel you may be watering them less than they need. You could segregate one or two and see how they respond to increased waterings depending on the weather you have.