I finally got my PowerBook 170 upgraded to System 7.5.5. I used the disk files from the Apple website. I was able to copy them to the hard drive via AppleTalk with my PowerBook G3. Then I ran the upgrade from the hard drive. It worked great. So far no problems. The unfortunate thing with my 170 is that the screen has growing case of "tunnel vision". The longer its on, the darker the corners of the LCD become. Eventually turning all back (about 1/8"). Its takes a while, about 45 minutes. Also Im having problems with my mouse. Occasionally, going right it not a option. If you push on the mouse ball, it goes. I have taken it apart and clean everything, but it doesn't to have fixed it.
Besides the hardware issues, I have been using it. It's a great word processor. I have been working on an outline and the 170 has zero distractions, no email, no internet. I am able to control my C-ADD (computer attention deficient disorder). Its easy to click on the browser when Im getting tired or stumped on something. Taking that option away actually helps.
I am using Mac Write Pro and saving it as text document. Opens and looks good on my MacBook Pro. All tabs and basic formatting look perfect. Saving in Mac Write can be tedious because you always have to select 'text' as the file type, if you don't it will convert it to Mac Write Pro format.
The 170 is very functional even at its age....