Usage: Get mesh_merge_tool.zip from the latest release install it and then in Edit mode use the new tool that appears in the left-side Toolbar. You can right click on the tool icon to set a hotkey for switching to the tool.
You can also choose to hotkey mesh.merge_tool in the Blender Preferences > Keymap > 3D View > Mesh > Mesh (Global) if you wish to call the operator directly instead of using the tool (NOTE: It is recommended that if you choose to do this then you should enable the "Wait for Input" checkbox when setting up your hotkey.
Click and hold the left mouse button on a vertex or edge and then drag it onto a second vertex or edge and release the mouse button to merge them. You can control whether to merge at the first or last vertex/edge, or the center between the two, via a dropdown in the Tool Settings bar at the top of the 3D Viewport, OR you can press the 1, 2, 3, A, C, F, or L key while dragging to change the merge location on the fly before you release the mouse button.
In vertex mode, if there is a starting selection and the tool is invoked on one of those vertices, then all vertices in the selection will be merged at the desired location.
Multi-merge, line and point size, and colors can be controlled from the add-on preferences.
Usage: object.context_select is automatically added to Blender's keymap when the add-on is installed (this can be disabled from the add-on's preferences after being installed).
Key entries are located in Blender Preferences > Keymap > 3D View > Mesh > Mesh (Global)
Default keys are double-click to set a new selection and shift + double-click to extend a selection.
LIMITATIONS:
Usage: Select edge(s) then search for Edges To Curve in the spacebar menu, or the Edges menu in the top of the viewport, or the Context menu, or hotkey object.edge_to_curve
Left Mouse confirms, Right Mouse cancels, Mouse Wheel increases or decreases resolution.
Usage: Select one curve and one object, then search for Duplicate Along Curve in the spacebar menu or hotkey object.duplicate_along_curve