I’ve installed the latest version but somehow my theme isn’t compatible. I use this them for my invoice and it has lots of modifications. So is there someone who can help me to get the installer of a previous version where the themes weren’t modified?
Only the latest update is available for download. Once you open the business with the latest update changes may be made to the database that would make it incompatible with a previous update.
Start by reading the guide on customizing themes. It may help.
And how old was the version you were using?
Please do not double post your questions. That reduces your chance of getting answers.