Welcome Stu,
Might be better to bring ALL 5 raw images into Adobe camera RAW converter and white balance correct all 5 in batch [select ALL] then make your changes. You can adjust the exposure there too along with fixing the chromatic abberation and vignetting. THEN save all 4 of them out on a single click 'save'. CS3 On the ACR 4.4.1 LENS tab for the Sigma 8mm Chromatic abberation and Vignetting I use these values
-44, +13, ALL, +100, +12.
Buying a new pan head might be done later, but first I would make sure you have the exact 'no parallax point'. Then I would rotate the lens UP at 90 [not 60] and shoot straight up on the 4th clickstop marker.
After stitching an equirectangular image... In panoweaver 5 suggest trying to convert it to a cube. That flattens the image [makes curved lines straight] save it as a cube - then open this cubed one in photoshop. zoom in to the zenith and nadir areas look and repair those small stitch issues. Then convert cubed back to equirectangular image.
How to deal with the lighting is interesting. In photoshop try using
image | adjustment | shadow/ highlight tool. What this tool does is it evaluates and locks in the highlights [ceiling wall lights] and then gives you an opportunity to brighten the shadows with out blowing out the highlights.
Example, beach, persons face in foreground - camera exposes for the bright sandy beach area behind the persons face. Result is properly exposed background sandy beach area and persons face is dark shadowed. Shadow highlight freezes the beach exposure and allows you to brighten the persons face.
I think centering the TW block is more of an html page code function.
I revisited your TW page and right mouse clicked "View Source"
There I found the html code that is placing your TW in the upper left corner. The body code is saying that the margins are around the TW block are all 0 or at 0 pixels. So left and top margin are a tight fit at the monitors edges.
<body leftMargin="0" topMargin="0" rightMargin="0" bottomMargin="0">
Im no html expert, and maybe someone else knows a better way but you can try replacing that code snippet with
<body topMargin="0">
<center>
Just a few thoughts
/s/
Dave
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EasyPano - Panoweaver
Pano2VR
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