Dyno lottery aside, when i had both my
MK2 Leon Cupra's, most modifications were tried and tested at some point, and measured on the same r/r (obviously on different days).
Standard car was 257bhp (2007 on BWJ engine) and 261 (2010 on CDL engine)
A full milltek and a carbonio intake on standard software gave less than 15bhp gain over stock.
Stage 1 on these parts, along with a DBilas intake, gave 321bhp. Stage 2 code plus an uprated pump gave over 350bhp when coupled with an S3 alloy end intercooler on moderate settings.
Long story short, i agree with the comments above - you need to make sure you know specified boost is being matched by actual and a whole bunch of other things which could detract from the power the car is capable of with the software installed.
Boost leaks, diverter valve not doing what it should be, shortage of fuel meeting specified amounts on stage 2+ (+ being the file originally designed for cars with uprated fuel pumps with supporting mods) etc etc etc.
Once that is done, and you know the car has a clean bill of health, i would be definitely considering a change of map to something tried and proven by many others by one of the more common tuners.