Im trying to install crossover office which i had in rpm format. I succesfully used
alien to convert it to .deb package. I installed as root using dpkg -i. The problem is that installed programs are only available for root. In c-office readme it is said that you can also instal it for only one user, but how can i install prog as user?

Yes you could install it in a user's home directory. However if the home directories are on a partition that is mounted with the -noexec parameter then it wouldn't run.

You can probably fix the system wide installation. The problem is probably file ownership and permissions. I don't have Crossover Office installed any longer so I don't have an example installation that works. Let's say that Crossover Office is installed in /opt/xoffice. Find the file ownership for the directory that holds the software and for the files in the directory.
If the files are owned by user root and group root then check the permissions for 'other' access on the directory and on the files. Let us know what you find.