hellou.
i assume that export task is for your store so those two scripts should deal with same problems.
im php/mysql/html programmer with over 13yrs of ecperience , specialised in osCommerce stores in general.
during that time i was working on stores with 1 product but also in music stores with 1.300.000+ products.
there had to support google sitemap, google merchant center feed - like the one you need, pricelist updates and import export functions.
to clarify ur need, every option given by u is defined in admin where user may input direct data - shippng cost, or field connected with given parameter. how u define categories ? al is simple option. do u want also added option to point specific categories that may be exported ?
if u r intrested we can talk on chat b4 u decide who to assign the job.
all the best,
Trygon eXtreme