This line doesn't work either with base paths. You must set the cwd:

	child = spawn(path.resolve(module.filename, '..', '..', 'tools','7zip', '7za.exe'), ['a', result, targets.map(function (p) {
		var x = p.indexOf(cwd);
		if (x >= 0) {
			p = p.replace(cwd, '');
			if (/^(\/|\\)/.test(p)) {
				p = p.substring(1);
			}
		}
		if (!p) {
			p = '.';
		}
		return p;
	})[0] + '\\*', '-tzip'],
	{ cwd : cwd });