CADSTAR PCB: Inaccurate import of arc tracks [unable to Select/Expand connection (U)]

Description

Arc track end points are not placed coincident with adjacent segments. This means that actions like "Select/Expand connection (U)" do not work as expected.

Steps to reproduce

1. Import attached cadstar design
2. Attempt to select/expand connection. Note that only a section of the track is expanded.

arc_track_minimal.cpa

KiCad Version

Application: KiCad PCB Editor

Version: (5.99.0-10079-g140f4a8d21), release build

Libraries:
	wxWidgets 3.1.4
	libcurl/7.74.0-DEV Schannel zlib/1.2.11

Platform: Windows 10 (build 18363), 64-bit edition, 64 bit, Little endian, wxMSW

Build Info:
	Date: Apr  1 2021 00:12:49
	wxWidgets: 3.1.4 (wchar_t,STL containers)
	Boost: 1.75.0
	OCC: 7.5.0
	Curl: 7.74.0-DEV
	ngspice: 34
	Compiler: Visual C++ 1928 without C++ ABI

Build settings:
	KICAD_SCRIPTING=ON
	KICAD_SCRIPTING_MODULES=ON
	KICAD_SCRIPTING_PYTHON3=ON
	KICAD_SCRIPTING_WXPYTHON=ON
	KICAD_SCRIPTING_WXPYTHON_PHOENIX=ON
	KICAD_SCRIPTING_ACTION_MENU=ON
	KICAD_USE_OCC=ON
	KICAD_SPICE=ON