HTML_Template_Sigma: Linebreak control

Hi In a template for the plain text section of a newsletter e-mail, it looks for example like this: <!-- BEGIN title_block --> -+-+-+-+- {title} -+-+-+-+- <!-- END title_block --> <!-- BEGIN hello_block --> Hello {firstname} {lastname} <!-- END hello_block --> <!-- BEGIN element_block --> <!-- BEGIN subtitle_block --> -+-+-+-+- {subtitle} <!-- END subtitle_block --> {text} <!-- END element_block --> Now, in default state, Sigma will trim all empty lines off. If I set the trim_on_save option to false, there will be too many empty lines, as the block defining lines seem to keep their newlines. I also want to leave the block structure, as there might be some variables not filled, and then I don't want according space and separator elements to be rendered. Is there a way to take full control of the newlines generated? (Without tricky template hacks... as template creation should be possible for people with little coding experience). Thanks for a comment! Markus