[Seven Skins]

Replace those variables with null and you will be left with , (comma) after the name.

						<vb:if condition="!$show['detailedtime']">
							{vb:rawphrase started_by_x_y_z_a, {vb:link member, {vb:raw thread}, null, 'postuserid', 'postusername'}, {vb:raw thread.postusername}, null, null, {vb:stylevar dirmark}}
						<vb:else />
							{vb:rawphrase started_by_x_y_z, {vb:link member, {vb:raw thread}, null, 'postuserid', 'postusername'}, {vb:raw thread.postusername},null, {vb:stylevar dirmark}}
						</vb:if>