Verifying that for both test cases the issue is no longer reproducible with the proposed packages. In other words, results with packages from -proposed are as described in ”Expected:” for each test case. (For both cases the issue was reproducible here with 1:0.9.7.0~bzr19-0ubuntu10.)

jani@saegusa:~$ LC_ALL=C apt-cache policy compiz-plugins-main compiz-plugins-main-default
compiz-plugins-main:
Installed: 1:0.9.7.0~bzr19-0ubuntu10.1
Candidate: 1:0.9.7.0~bzr19-0ubuntu10.1
Version table:
*** 1:0.9.7.0~bzr19-0ubuntu10.1 0
500 http://archive.ubuntu.com/ubuntu/ precise-proposed/main amd64 Packages
100 /var/lib/dpkg/status
1:0.9.7.0~bzr19-0ubuntu10 0
500 http://archive.ubuntu.com/ubuntu/ precise/main amd64 Packages
compiz-plugins-main-default:
Installed: 1:0.9.7.0~bzr19-0ubuntu10.1
Candidate: 1:0.9.7.0~bzr19-0ubuntu10.1
Version table:
*** 1:0.9.7.0~bzr19-0ubuntu10.1 0
500 http://archive.ubuntu.com/ubuntu/ precise-proposed/main amd64 Packages
100 /var/lib/dpkg/status
1:0.9.7.0~bzr19-0ubuntu10 0
500 http://archive.ubuntu.com/ubuntu/ precise/main amd64 Packages