The default view under any skin of a single blog did not provide any simple clear link to add a new post; it was necessary to scroll down the right menu to find an "Admin" entry, and then click on that to make a post. I trawled through the code to figure out how to do this, then added appropriate code (slightly different in different skins) to all of the _main.php skin files (not including the RSS feed skins).

Files changed:

blogs/skins/basic/_main.php
blogs/skins/bluesky/_main.php
blogs/skins/custom/_main.php
blogs/skins/guadeloupe/_main.php
blogs/skins/natural_pink/_main.php
blogs/skins/nifty_corners/_main.php
blogs/skins/originalb2/_main.php
blogs/skins/wpc_aubmach/_main.php
blogs/skins/wpc_default/_main.php