sharepoint-workflow

I'm using MOSS (SharePoint 2007 Enterprise), 32-bit, SP2. I've been noticing some odd problems with Custom Workflow Activities which I've developed and am using in SharePoint Designer (SPD) workflows. These actions seem to work correctly, but don't "play nice" with the rest of the workflow (specifically, the root issue was posted at: Timing concerns with Custom WF Activity changing permissions , since that hasn't gotten any responses I've been digging deeper...) To help pin down the problem, I've developed a very simple test, which I will outline in detail below, and am noticing even more odd

I have created a workflow is SharePoint Designer and associated it with a list. The workflow creates an approval process, so SharePoint creates a task in the Tasks list so that the user can approve or reject. What I need to do is to approve or reject the task without opening the task in the task list. After some research I figured that I can use SharePoint Web Services. However I feel lost as I don't know which service, e.g. Lists.asmx, and which method, e.g. UpdateListItems, to call. Can someone guide me through the following: 1- Is it feasible to approve a workflow task SharePoint Web