Import csv as Products upgrade – something wrong. PS 1.5.4

[Boris726]

Hello,
I'm trying import of csv file (products) which was bases on the sample.

Only Four fields are filled in the file:
- Active (0/1)
- Name*
- Price tax excl. Or Price tax excl
- Reference #
Others fields are empty.

Delete all ___ before import: NO
Use product reference as key: YES
On the screen with the data mapping ALL empty fields set as Ignore.

The four fields above updated fine after import. Features and pictures with no change but other fields were cleared. What's wrong with the import?

 

Thank you.