Brick&Seed block code.

[Virus]

Give these a try:

Seed Blocker

E2000500 00000024
4B058821 DB034299
42994B04 8001DA00
1C082101 47184B02
00001000 00004BA4
020375B0 00000000
020375A8 47084900
020375AC 02000501

Read-Only Town

120375AA 000046C0

Use only one at a time. Read-Only Town should prevent ANY changes.
I'll fix up the seed blocker code later (if it works).

Edit: You will most likely notice a couple of issues with the seed blocker (which I can fix later).
1. Flowers can not be planted.
2. Items cannot be removed from your town (you get a "copy" of the item if you pick one up).