yes to both,.. mostly.
1) the progress dialog, you can ‘request’ that drivers not show their progress dialogs. read heavily ‘request’, controlled with the bShowProgress parameter many devices that I work with honor the request and do not show their progress dialogs, but as with all things twain – some drivers just don’t play well with others. ymmv
2) yes. as long as you are using a UiThread (a thread with it’s own message pump – not a worker thread) you shouldn’t have too many problems.
Usually these are things you must solve when you’re looking for automation with twain – solutions where you are looking to acquire from the command line, from a windows service or from another different computer. In those cases once you solve these first two points you get to solve another nastier problem, ‘How do you make the error dialogs go away’, as while you can request that the progress dialogs not be shown you cannot request that the error dialogs not be shown. The error dialogs for when any number of things happen, attempt to acquire when the device isn’t on, get a paper jam, etc.
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