Which application are you using?
I have a website www.casanor.com made in Muse. It is running from there where i link to the catalog.html.
Catalogue produced in InDesign and eksported as .swf interactive
Usually, the SWF is only the player and the data to load is external, like PDF pages. It seems, your entire catalog is one huge SWF, so it loads first, then plays. There are far better Flash/PDF solutions for catalogs out there than to convert from Indesign to SWF.
I will find another solution where i still can make an animated/interaktive catalogue.