recent MacOS X scanner support architecture, and how set some key defaults

I sporadically use a EPSON Perfection 1200U USB-connected scanner on MacOS going back quite a few years. I imagine this query applies to users of many other common scanners as well.

Some time ago -- I guess when I first installed 10.7-- the EPSON scanning app stopped working. Momentary panic, until I found that MacOS now included "EPSON Perfection 1200.app" which replaces the EPSON scanning app reasonably well. Most of the time I launch it as a stand-alone by doing a Spotlight search for "EPSON" and looking for "EPSON Perfection 1200.app". And I'm generally OK with this, except:

o Sometimes the Spotlight search fails to find the app, which puzzles me.

o Recently, I don't seem to be able to set two key preferences, namely the default resolution and always putting scans in my choice of folders (namely ~/scans). Up until --I dunno-- six months ago, this worked, those preferences "held". Now they don't. The default resolution is now 50dpi, a completely useless value in my view. I usually want 300dpi.

The best docs I can find about this "latest" scanning support is in "Mac 101: Using a Scanner", here:

http://support.apple.com/kb/HT4505?viewlocale=en_US&locale=en_US

This tells me that I can scan from "various applications" including Image Capture, Preview, and Print & Fax Preferences. I guess that such apps spawn specific scanner apps such as "EPSON Perfection 1200.app" as a child (subordinate) process. I didn't see anything about using "EPSON Perfection 1200.app" stand-alone.

I feel like understanding the recent scanner support architecture might help me understand why I sometimes can't find the stand-alone app and why I can't set the key preferences I list above. Maybe there's another document, a more technical one, that can help?

Meanwhile, I looked at the preference files that might be applicable:

~/Library/Preferences/com.epson.scan.standalone.plist

~/Library/Preferences/com.epson.scanner.ica.plist

~/Library/Preferences/com.apple.Image_Capture.plist

Just guessing from the naming, the first applies to the app used standalone, and the second the app is spawned from an "Image Capture Application". The third is for the presumably canonical parent app, "Image Capture. I opened all three in Xcode... I found nothing in any that explains the default resolution of 50 dpi I observe, and no preference for the default folder where new scans should be stored.

One factoid: I found the app EPSON Perfection 1200.app" in ~/Library/Printers. I guess when MacOS discovers a powered and connected USB scanner, it identifies the scanner, and copies its driver-app to the user's "installed" list. That makes perfect sense, except the name of this directory specifies "Printers". There's no ~/Library/Scanners. Is this simply a harmless hack, classifying a scanner as a printer?

Suggestions? Am I totally overlooking some real obvious stuff?