Here is a first draft of a droplet which I have used to import Taskpaper files to Omnifocus.
If you download and unzip the droplet, you should find that dragging and dropping a taskpaper file onto it will lead to a basic import.
Tasks in the file which are either not preceded by a project heading, or are under the heading "Inbox:" are placed straight in the Omnifocus Inbox.
Other projects and tasks are placed in a date-stamped import folder which you will find at the bottom of the project sidebar.
In addition to files created with Taskpaper, this should in principle work with any plain .txt file in which actions are preceded by "- ", project header lines end with ":" and context labels at the end of a line begin with " @"
Plain lines which begin without a dash and a space are interpreted as notes if they are preceded by an action line or a project line, and as inbox items otherwise.
(However, a draft only, and may not work with your data - intended simply for reference. No warranties, implicit or explicit)
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