I'm having some problems with the DialogComponentDoubleRange and perhaps with SettingsModelDoubleRange. Obviously this dialog component doesn't have some of the controls including field with and spin increment. More importantly my initial investigation suggests that lower and upper bounds of 0 and 10 are being used for the validation whereas I would have expected only min <= max to be applied. Has any-one else had experience of this dialog component?

You are absolutely right: this is a bug. So far, there is no possibility to specify min and max values for the spinners (and also not the step size).
We apologize and are currently fixing this bug. The bugfix will be available with the next version KNIME 1.3, which will be released in November. Hope, you can wait that long. If not: tell me and we will find a solution to include a patch with the bugfix.