I am participating in a project with ASE CE with two nodes.
Still project is before go life so "Judgment Day" will come 
But we have quite good situation because we have 4 user databases and we devide them into 2 nodes trying to get good balance.
So we won't have one database that is operated bu two nodes in the same time.
I tried to find some real good document about monitoring and tuning ASE CE key places but there is no such information.
I need good monitoring in case that we have to use one database on 2 nodes (pessimistic option)
I plan to script all this alone and test on some real scenarios.
We faced with some bugs in ASE CE version but as I check ASE CE SP121 some of them are fixed.
In my opinion if you have to use one database with 2 or more nodes in the same time you have to "partition" your aplication as much as you can.
And then try to make many tests.
There is quite good document about best practices (but nothing about monitoing).
http://www.sybase.com/files/White_Papers/Linux-ASE-CE-Best-Practices-Guide-WP.pdf
Very important is thing about IO fencing.
To setup this you have to read documentation very carefully.