I am hosting my .css stylesheet in the design studio and have included a link to it in the html of my landing page.
Marketo seems to be registering that, the .css file is hosted within marketo and it's giving it a root name when the page renders. eg. /index.php/038946532905642
This is causing the html file to not recognise the .css file.
I also had this working for a while and then all of a sudden it stopped. (Started changing the .css files name)
Any help would be great?
There's definitely a bug here. Open a support case to get it fixed. From what I can see, Marketo is trying to fetch assets via its internal proxy (similar to the secure image proxies used by Outlook.com and Google) but failing to readjust when the LP is published.