Well, I solved this problem by changing the Bauhaus theme’s style.css file. If anyone is interested, these are the modifications I had to make in wp-content/plugins/wptouch/themes/bauhaus/default/style.css:
body { background-color: #f9f9f8 !important; }
This should match the colour you pick for the body background in the plugin’s settings. For some strange reason the body gets given an inline style to match the header’s background, so you have to override that or you get the wrong background when scrolling to the right. Then find:
.post-page-content {
color: rgba(0,0,0,.7);
font-size: 100%;
line-height: 165%;
padding-bottom: 50px;
}
so remove overflow: hidden from there.
I also removed max-width: 100% from .post-page-content table but I don’t know if that had anything to do with it.
I can now scroll to the right if the table overflows, and the rest of the layout seems unaffected.
The plugin’s authors mention “you may add custom styling in the Stats & Custom Code area of your WPtouch admin panel” so perhaps it would be best to enter the modified CSS code there rather than modifying the plugin’s files. Either way this seems to do the trick.