We have been using Open Office 3.0 in our office & we are facing couple of 
issues regarding open office, as listed below :

1) Major proble which we are facing is saving a file(spreadsheet) which is 
opened Simultaneous by 2-4 users.The problem is if any one who has opened the 
file first is able to save the changes while the rest depends but most of the 
chance it dosn't get changed as it shows that file have been saved but when 
you close it & reopen it the altered data is lost or some time it dosn't allow 
to save the changes by giving errors(user dosn't have sufficient rights to 
save the file),

2)While opening a excel or spreedsheat file by multiple user it opens the file 
in read-only mode for other users except the first user who has opened the 
file.