Could some one please help with the following queiry/

Iam currently playinTR ANNIVERSARY and have reaached the central chambber in the tomb of q---pec.Lara is supposed to run to the opposite enterance where a large stone bouler sits. On dislodging the bouler it crashes thro; the centra chamber floor, revealing a support platform. It shoould also disslodge a ceiling support that she can shoot with her pistols BUT THI IS NOT HAPPENING