fix issues

- fix nullptr name assignment error on CKObject.
- remove slot check for CKTexture::GetFileName in BMap. return nullptr, not throw error when no slot to get file name.

BMap/BMExports.cpp

@@ -371,8 +371,6 @@ bool BMTexture_GetFileName(BMPARAM_OBJECT_DECL(bmfile, objid), BMPARAM_OUT(LibCm
 	auto obj = CheckCKTexture(bmfile, objid);
 	if (obj == nullptr) return false;
 
-	if (obj->GetUnderlyingData().GetSlotCount() == 0) return false;
-
 	BMPARAM_OUT_ASSIGN(out_filename, obj->GetUnderlyingData().GetSlotFileName(0));
 	return true;
 }

LibCmo/CK2/ObjImpls/CKObject.cpp

@@ -5,9 +5,12 @@ namespace LibCmo::CK2::ObjImpls {
 
 	CKObject::CKObject(CKContext* ctx, CK_ID ckid, CKSTRING name) :
 		m_ID(ckid),
-		m_Name(name),
+		m_Name(),
 		m_Context(ctx),
-		m_ObjectFlags(CK_OBJECT_FLAGS::CK_PARAMETERIN_DISABLED) {}
+		m_ObjectFlags(CK_OBJECT_FLAGS::CK_PARAMETERIN_DISABLED) {
+		// set name with possible nullptr.
+		XContainer::NSXString::FromCKSTRING(m_Name, name);
+	}
 
 	CKObject::~CKObject() {}