header line (with field names) is ignored
Yes. Use the list on the top right to define the fields.
content of many "payee" fields is ignored
Do you mean the payee field on the op right list is properly lined-up and checked but finally not imported in the Preview when you click on the Preview button?
- source file has both "transaction type" and "comment" fields. Content of "transaction type" is put into "comment", and actual comment is lost
Are you sure you are lining-up fields properly on the top right list? iCash simply imports the data the way you tell it to do.
- even worse: decimals are ignored for "amount": "63,75" is read as "63,00"
Does your iCash decimal settings corresponds to both your system settings and your file settings?
I thought this all might result from a text encoding problem, so I changed from 'none' to 'utf8'. This made things worse.
No, encoding only affect accentuated characters.
"Transaction type" was still set to "Unknown", with one exception.
iCash has a defined list of transaction types, does it match your file? This list is editable. Personally I prefer not to modify it and use the rule editor.
What is going on??
Perhaps it is a problem with your file, is it a real valid CSV? I have seen many banks calling whatever thing a CSV file.