QB Issue Resolution:

There are 3rd party apps that work with Windows files.  However, I’m pretty sure you cannot import transactions into a QB Mac file.

You may want to get good year end balances and start 4 new company files for 2016.  You can export / import lists to help start the new files.

Resolution for Issue 'I want to separate the 4 different classes of a company file into 4 different company files.' available: Yes (Solved).
Source: Intuit Community forum.

I want to separate the 4 different classes of a company file into 4 different company files.: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

Support for classes
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Error Recovery for classes [Canada]
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