First try changing your scan rules to this:
-* +*.css +*.jpg +www.holiday-rentals.co.uk/p*
(You'll incidentally get something on Portugal that way...)

I also:
-set mirror depth to 2 and external depth to 0
-checked attempt to detect all and get non-html files related
-checked no error pages and no external pages
-set spider to no robots.txt rules
-added this to the url list:
<http://www.holiday-rentals.co.uk/search/spain/region:58/minPrice/8000/currency/GBP/page:2>


This is what my logfile, line 2, was:
winhttrack -qwr2%e0C2%Pnxs0u1%s%uN0%I0p3DaK0H0%kf2o0A50000%f#f -F "Mozilla/4.0
(compatible; MSIE 6.0; Windows NT 5.0)" -%F  -%l "en, en, *"
<http://www.holiday-rentals.co.uk/search/spain/region:58/minPrice/8000/currency/GBP>
<http://www.holiday-rentals.co.uk/search/spain/region:58/minPrice/8000/currency/GBP/page:2>
-O1 "R:\Misc.III\My Web Sites\test1" -* +*.css +*.jpg
+www.holiday-rentals.co.uk/p* 

Seemed to work. Hope I didn't miss anything to tell you.

HTH,
B^D