In order to import transactions you need to create first the needed categories and accounts. It has to be done in this order, categories, accounts and then the transactions. This can be done manually or through imports. If you want to do it with imports and you don't have those files available you should create them with excel, save the sheets as text and import them to iCash. When we started using iCash for our own accounting we did it this way, opening our transaction file with excel and adding lacking data to it and then copying and pasting them to a different sheet. Don't worry if you repeat a category again and again, iCash will create it once.
The category file is made of two fields: category type and category name. Available types are "Banks", "Incomes", "Expenses", "Debts", "Portfolio", "Assets" and "Startup". The account file is made of 3 fields: Account type, account category and account name. To see an example of such files you can create a default iCash document and export categories, accounts and transactions.
If you prefer to use QIFs, just export categories, accounts and transactions in separate files (Quicken allows this) and import them back in the same order to iCash.
WAIT! In order to add a comment below just use your Facebook, Google+, Twitter or Disqus login data.