FM2015 - Responsive HTML5 - Anchored frames in conditions don't align properly

I have a document (well, many documents) that includes print-quality images.

When publishing to html5, the images are downsampled into jpgs (that's fine), but the quality is not as good as when I create my own lower-res JPGs of the images.

So... where I have an anchored frame with a high-res image, I put it in a 'print only' conditional tag, make a copy on the next line and put the low-res image into *that* frame with an 'html only' conditional tag.

Some of these frames are in indented paragraphs, some are not. I want the frames to follow the indentation level. I found that I needed to set the frame to be 'At Insertion Point' (if I used 'Below Current Line', I had to use specify alignment (left / right/ closest to binding/ farthest from binding), which are not appropriate).

However, when I mark the paragraph (with the frame) as conditional ('html only') and publish, the image *right justifies* on the web page instead of left justifying at the indentation point (e.g. on a non-indented paragraph format, image should align at left edge of text frame. On an indented paragraph format, image should align at the left indentation point).

Am I misunderstanding how to do this? Any solutions?

Thanks.