This isny much of a hack but well here it is.
Camtasia for free - works with 7.
[You must be registered and logged in to see this link.] download there.
Then Install, while installing it will ask you for a code - it worked for me and let's hope it works for you!
Keys:
G4DCD-9CC5J-JTDPC-FQJ9X-X735A
HLCZF-HDCPL-KGB6W-ZSCAZ-VF6A2
CD2AA-QZBHD-C3KJL-E9HRV-Q797C
*Note:Only Need One LOL*