as for (b) its a known bug ... the needed settings are inside theme.rc and i already talked to the dev of tasks on what to ... he stated that it maybe is caused by hooking tasks into a label - so if it will highlight when not hooked he might be able to fix this - didnt get a chance to test it yet tho ... my exams are eating up spare time

(a) i noticed that too sometime - but i hardly ever use more than 10 apps and its not limited by the code either [at least not for your resolution] but maybe it has to do with the hooking too
well, i thought about changing to xTaskbar anyway coz of these strange bugs and to realize this erlier mentioned bigger taskbar with optional text to display alongside with the task tiles ... so stay tuned for updates
expect some in about 2 weeks