Engineering support services company Redhall Group made "substantial progress" with the implementation of its strategic plan during the six months to 31 March, but failed to impress after reporting continued delays on major customer, nuclear-related projects in the manufacturing business.The issues, caused by budgetary constraints and design delays, contributed to a reduction of revenue to £41.4m compared to £50.6m in the same period last year, while losses widened to £8.81m from £0.2m.A protracted downturn in the oil and gas sectors has also contributed to a reduction in volumes and profitability, it said.The specialist services businesses broke even in the first half, with revenue affected by reduced volumes and a conservative margin take in its Redhall Marine business. However, the division is expected to provide a higher level of profitability in the second half, based on the level of orders it expects to secure."The execution of high margin work in our Manufacturing businesses is at the heart of our strategic plan," chairman Martyn Everett said."A number of projects secured during the first half have demonstrated our capability to deliver complex projects for our key customers and we anticipate an enhanced level of profitability in the second half of the year."The share price had declined 6.98% to 10p by 10:26.