diff --git a/packages/ui5-tooling-modules/lib/middleware.js b/packages/ui5-tooling-modules/lib/middleware.js
index e927e9d8..3817695a 100644
--- a/packages/ui5-tooling-modules/lib/middleware.js
+++ b/packages/ui5-tooling-modules/lib/middleware.js
@@ -156,15 +156,15 @@ module.exports = async function ({ log, resources, options, middlewareUtil }) {
 				moduleName = moduleName.substring(0, moduleName.length - 3);
 			}
 
-			// check if the resource exists in node_modules
-			let resource = getResource(moduleName, { cwd, depPaths, isMiddleware: true });
-			let existsPackage;
-			if (!resource) {
-				// in some cases there is a request to a module of an NPM package and in this
-				// case we still need to trigger the bundle and watch process to create the
-				// bundle info from which we can extract the resource (e.g. webc libraries)
-				const npmPackage = getNpmPackageName(moduleName);
-				existsPackage = !!resolveModule(`${npmPackage}/package.json`, { cwd, depPaths, isMiddleware: true });
+			// in some cases there is a request to a module of an NPM package and in this
+			// case we still need to trigger the bundle and watch process to create the
+			// bundle info from which we can extract the resource (e.g. webc libraries)
+			const npmPackage = getNpmPackageName(moduleName);
+			const existsPackage = !!resolveModule(`${npmPackage}/package.json`, { cwd, depPaths, isMiddleware: true });
+			let resource;
+			if (existsPackage) {
+				// check if the resource exists in node_modules
+				resource = getResource(moduleName, { cwd, depPaths, isMiddleware: true });
 			}
 
 			// if a resource has been found in node_modules, we will
diff --git a/packages/ui5-tooling-modules/lib/rollup-plugin-webcomponents.js b/packages/ui5-tooling-modules/lib/rollup-plugin-webcomponents.js
index d0866e40..c4807ad5 100644
--- a/packages/ui5-tooling-modules/lib/rollup-plugin-webcomponents.js
+++ b/packages/ui5-tooling-modules/lib/rollup-plugin-webcomponents.js
@@ -111,6 +111,7 @@ module.exports = function ({ log, resolveModule, framework, skip } = {}) {
 			let modulePath = resolveModule(source);
 			if (modulePath) {
 				modulePath = modulePath.substr(metadata.npmPackagePath.length + 1);
+				modulePath = modulePath.replace(/\\/g, "/");
 				const moduleName = `${npmPackage}/${modulePath}`;
 				const clazz = WebComponentRegistry.getClassDefinition(moduleName);
 				// TODO: base classes must be ignored as UI5Element is flagged as custom element although it is a base class
@@ -227,7 +228,7 @@ module.exports = function ({ log, resolveModule, framework, skip } = {}) {
 					designtime: `${ui5Metadata.namespace}/designtime/${clazz.name}.designtime`, // add a default designtime
 				});
 				const metadata = JSON.stringify(metadataObject, undefined, 2);
-				const webcClass = moduleInfo.attributes.absModulePath; // is the absolute path of the original Web Component class
+				const webcClass = moduleInfo.attributes.absModulePath.replace(/\\/g, "/"); // is the absolute path of the original Web Component class
 
 				// Determine the superclass UI5 module name and import it
 				let webcBaseClass = "sap/ui/core/webc/WebComponent";
diff --git a/packages/ui5-tooling-modules/lib/util.js b/packages/ui5-tooling-modules/lib/util.js
index 2a5ce434..7f4b51c3 100755
--- a/packages/ui5-tooling-modules/lib/util.js
+++ b/packages/ui5-tooling-modules/lib/util.js
@@ -245,6 +245,7 @@ module.exports = function (log, projectInfo) {
 	 */
 	function resolveNodeModule(moduleName, cwd = process.cwd(), depPaths = []) {
 		let modulePath;
+		//let millis = Date.now();
 		const resolve = function (moduleName, options) {
 			try {
 				return require.resolve(moduleName, options);
@@ -270,6 +271,7 @@ module.exports = function (log, projectInfo) {
 			});
 			if (modulePath) break;
 		}
+		//console.log(`resolveNodeModule filter took ${Date.now() - millis}ms`, moduleName);
 		return modulePath;
 	}
 
@@ -710,7 +712,7 @@ module.exports = function (log, projectInfo) {
 			} else {
 				// derive the module path from the package.json entries browser, module or main
 				try {
-					const pkgJsonModuleName = path.join(moduleName, "package.json");
+					const pkgJsonModuleName = path.posix.join(moduleName, "package.json");
 					const pkgJson = require(pkgJsonModuleName);
 					const resolveModulePath = function (exports, fields) {
 						for (const field of fields) {