E-Newsletter does not differentiate between {USER_NAME} and {FIRST_NAME} ?

I have difficulties having e-newsletter pick the right values for username and firstname.
Currently our WP-Users are correctly entered with frist name, last name and of course username. Incase we csv-import data, your sample.csv offers, how to do that.
So I thought - we simply could pick WP-Username and WP-Firstname to use them for e-newsletter. But the plugin picks USER_NAME Value also for FIRST_NAME - we need them separate.
Also the {DATE} value will not be filled with data.

pls review our used code for USER_NAME in newsletter content area:

		<td style="text-align: right;"><br />City, {DATE}<br /><br />...<strong>{USER_NAME}</strong></td>

used code for FIRST_NAME in newsletter content area:
<p style="font-size: 12px;"><br />Hey {FIRST_NAME},</p>

how to solve that quickly? br rob