Altium Project Importer: fails if schematic / pcb files are in subfolder: crash

Description

@sethhillbrand follow-up to #20161 (closed)

Steps to reproduce

  1. download project from #20161 (closed)
  2. unzip it
  3. try to import it via kicad -> File -> Import Non-Kicad-Projects
  4. select as output folder a folder not in the project folder, for example
C:\Users\test\Downloads\ixora-v1.3-altium-project__1_\Ixora V1.3 Altium Project\kicad

while the Altium Project is located at

C:\Users\test\Downloads\ixora-v1.3-altium-project__1_\Ixora V1.3 Altium Project\Ixora V1.3
  1. it crashes during schematic import

image

Sentry ID: 13649254-30e9-42bb-99ef-d943ff6399bc

KiCad Version

Application: KiCad Schematic Editor x64 on x64

Version: 9.0.5-45-g8a5c51d37f, release build

Libraries:
	wxWidgets 3.2.8
	FreeType 2.13.3
	HarfBuzz 10.2.0
	FontConfig 2.15.0
	libcurl/8.13.0-DEV Schannel zlib/1.3.1

Platform: Windows 11 (build 26100), 64-bit edition, 64 bit, Little endian, wxMSW
OpenGL: Intel, Intel(R) Iris(R) Xe Graphics, 4.6.0 - Build 32.0.101.6737

Build Info:
	Date: Oct  6 2025 05:44:22
	wxWidgets: 3.2.8 (wchar_t,wx containers)
	Boost: 1.88.0
	OCC: 7.9.1
	Curl: 8.13.0-DEV
	ngspice: 45.2
	Compiler: Visual C++ 1944 without C++ ABI
	KICAD_IPC_API=ON

Locale: 
	Lang: en_GB
	Enc: UTF-8
	Num: 1,234.5
	Encoded кΩ丈: D0BACEA9E4B888 (sys), D0BACEA9E4B888 (utf8)