anyone have Infa-Secure Exceed EHP Convertible Booster Seat? trouble installing

OK Ladies I really need some help with this.


So MIL brought a Infa-Secure eXceed EHP Convertible Booster Seat as DS is just over 2 and 15.5 kgs so it wasn't really worth her buying a childseat when he would more then likely outgrow it and he has to be in a booster seat until he is 7 or outgrows them. She has a station wagon Toyota stationwagon that is about 8 yrs old.

We tried installing it today, in the middle seat position, and it just isn't sitting right. The seatbelt isn't a lapsash (it's a shame it would have worked perfectly) it comes from a point in the roof and works like a normal seatbelt and it keeps pulling the childseat up.

Any ideas/help/anyone else have these problems?

Anyone want to buy it? cause if I can't get this sorted we are going to have sell it and get a different model.

TIA