After starting a line and setting a colour, you might try saving your preferences (Ctrl-S or File, Save Preferences).
The only thing I can think of that really changed recently that could effect this is the conversion to XML preferences.
From showeq.xml:
Code:
<section name="MapMgr" >
<property name="DefaultLineColor" >
<string value="gray" />
</property>
<property name="DefaultLineName" >
<string value="line" />
</property>
</section>
Now to dig into the code and find the defaults for new locations...