I have tried all the J2ME book readers that I have been able to find on my A1200 - ReadManiac, BookReader, Mobile Bookshelf, Microreader - but they either do not even start or they need hardkeys to work properly.
The only two that I have found that do work on the A1200 are:
TequilaCat Text reader
This ebook reader was written by a Russian programmer and has a lot of functionality - but can only handle text (.txt) files. You download a program from his website that you have to run on your PC to create the correct jar file for your phone. The latest version, 2.2.8, is meant to be able to let you create a java applet that has file support (ie you can open and read text files located on your SD card) - but I could not get that version to work - it just started then crashed. (I tried both Phone Model = "Motorola MIDP2 (file support)" and "MIDP 2.0 + JSR75 (file support)" - but neither worked. I also changed the apps permissions to "Domain: Manufacturer" - but still always crashed on startup!!
I could only get it to work on the A1200 by selecting Phone Model = "MIDP 2.0" - which means you have to package the text file(s) that you want to read with the jar file using this program and then install it on your phone. This means you have to create a new jar file for every new book you add.
I have attached a jar file containing a Dan Brown novel in Spanish for you to try out.
Keys are
• Joystick click = Display Menu
• Joystick Up = Page Up
• Joystick Down = Page Down
• Upper Left side button = Scroll line Up
• Lower Left side button = Scroll line down
• Joystick Right = Change Font
• Joystick Left = Turn on Auto scroll.
[When creating the jar file it allows you to re-assign functions to the joystick and to the upper and lower side buttons (codes =-30 and -31)].
Other than the pain of converting docs into .txt format and then packaging them into a jar file and installing it - I found it works really well. It is much easier to read with than Viewer because:
• its paging is great and you can even turn on auto-paging so it changes automatically.
• it remembers where you are in the book next time you open it up which is very handy.
• it has a great search function - so I have put my company phone book on the phone using this.
• allows you to create whatever fonts and/or colors you want for viewing the file in when creating the jar file

Do not try to use the Key Lock or Backlight functions in the menu. These both turn off the backlight on the A1200 making the screen go totally black. The only way to get going is to turn the phone off then on again. (Does not harm the phone - it is just a pain)
See
http://tequilacat.nm.ru for download and good Help File that explains how to use it in detail.
If anyone is able to get the version that can read files on the phone working let me know!
Anyview
This is a Chinese ebook reader and works really well on A1200
BUT only Chinese version exists so all menus are in Chinese - but I was able to figure most of them out pretty easily. The file can be obtained from the Downloads section and this
thread has instructions and screenshots that show translations of the menus. It can read text files from your phone so is good for files that you can not be bothered creating a Jar file to read with TequilaCat.
The badside is that on my phone (FW = .8p Bint plus) it can not read Spanish text - it displays Chinese characters instead of the spanish letters (See screen shot) - so think my phone's Character Set must be set to one with Chinese characters rather than ISO-8859-1 (Western Europe).
Does anyone know if I can change something on my phone to fix this?? I assume this would not be an issue on the A1200i??